Automotive transmission control



Aug. 11, 1953 G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL 15 Sheets-Sheet 1 Filed March 18, 1948 \QN Qu INVENTOR: Glenn 7'. Randal,

ATTORNEYS.

Aug. 11, 1953 G. T. RANDOL 2,648,232

AUTOMOTIVE TRANSMISSION CONTROL Filed March 18, 1948 2 15 Sheets-Sheet 2 I I m; INVENTOR- Lr ,1 i 2 Glenn 7? Randal,

i, V Y 2 M7 EC i I ATTORNEY-5'- '/4] lmuimi 15 Sheets-Sheef s INVENTOR: Glenn 7'. Randal, BY 2 W 1 W,

ATTORNEYS.

G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL Aug. 11, 1953 Filed March 18, 1948 1953 Q G. T. RANDOL 2,648,232

AUTOMOTIVE TRANSMISSION CONTROL Filed March 18, 1948 l3 Sheets-Sheet 4 E iifllll Iflll' I .7416 206 36/ J47 a; 99 703 aa H0 200 11v vs NTOR Glenn 7'. Randal,

BY 57 7 ATTORNEYS.

Aug. 11, 1953 G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL 13 Sheets-Sheet 5 Filed March 18, 1948 INVENTOR: Glenn 7. Randal, 757W v ATTORNEYS.

5 G. T. RANDOL 2,648,232

AUTOMOTIVE TRANSMISSION CONTROL Filed March 18, 1948 15 Sheets-Sheet 6 Glenn 7'. Randal,

INVENTOR:

I 9 bw I i N 37M 1 I j ATTORNEYS.

Aug. 11, 1953 G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL 13 Sheets-Sheet 7 Filed March 18, 1948 ALE.

VINVENTOR: BY Glenn T. Randal,

ATTORNEYS.

Aug. 11, 1953 G. T. RANDOL 2,648,232

AUTOMOTIVE TRANSMISSION CONTROL Filed March 18, 1948 13 Sheets-Sheet a slum-"m 4 sli I iiliill 1N VENTOR Glenn 7'. Randal,

W? W ATTORNEYS.

G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL Aug. 11, 1953 13 Sheets-Sheet 9 Filed March 18, 1948 INVENTOR Glenn 7. Randal,

W ATTORNEYS.

5 G. T. RANDOL 2,648,232

AUTOMOTIVE TRANSMISSION CONTROL Filed March 18, 1948 I 15 Shets-Sheet lO INVENTOR: 1. Glenn T. Randal,

FWMW

ATTORNEYS. f

Aug. 11, 1953 e. T. RANDOLY AUTOMOTIVE TRANSMISSION CONTROL l3 Sheets-Sheet 11 Filed March 18. 1948 ATTORNEYS.

llllllilrv m a 4 "mm; J a 1 5 a! I 3 9r. 5 2 H5 a o a t w d.\i/ 9 1. J 1 V a Q in W W o a W,,\./, L LL 1 5 a r... m f ,4. v x a iami 1 U5 6.555 HM 7 M a 3 3% G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL Aug. 11, 1953 1a Sheets-Sheet 12 Filed March 18, 1948 INVENTOR:

w mvw G. "r. RANDOL AUTOMOTIVE TRANSMISSION CONTROL Aug. 11, 1953 13 Sheets-Sheet 13 Filed March 18, 1948 INVENTQR:

Glenn T. Randal,

ATTORNEYS.

i atented Aug. 1 1 195 3 UNITED STATES PATENT OFFICE -73 Claims. 1

This invention relates toa transmission control, and particularly to a control for regulatin the operation of a power'means that is shiftable to effect changing the speed ratios between a driving member or shaft and a driven member or shaft. A particular aspect of this invention relates to a control for a power-operated overdrive mechanism employed on motor vehicles.

In a further and more specific aspect this'invention relates to a control for a power shifting means that willestablish two speed drives for an automobile or like vehicle, especially where the two speed drives are obtained by an overdrive mechanism, and where thecontrol is actuated by particular operations of conventional drivermanipulated elements of the automobile thata're found in the driving compartment-thereof.

Broadly, an object of the invention is-to provide a control of the foregoing type that isoperatedby readily understandable manipulations oftheconventional control elements of the-vehicle, which control elements include a hand shift control member, an accelerator pedal and a=clutchpedal.

Another object of the invention is to superpose the controls of the power shift upon prede-' formedwithout involving operation of the final power shifting means; and more particularly so that the power shifting means can be-operat'ed only after the conventional shifting hasproceeded to a given point, establishing one of its speed ratios with inhibition of power shift at any other point in the manual or conventional operation. This object is especially pertinent to a combination of a multispeed drivepower transmission with an overdrive, toprevent superposition of overdrive on low speed'drives.

Another object of the invention is to interconnect the control for the power shifting vmeans with the hand gear shifting lever and. one ofthe other operator-controlled elements, and especially the accelerator pedal, wherein the hand shift element is movable to a regular position to establish one speed drive, and is movable toaposition .It is afurther object of .the present invention to provide 'a transmission control-utilizing a plurality of personally-operable control membersto selectively establish one .of l a plurality of v speed drives.

.Anaddit'ional objectisto provide a transmission control utilizing ,a plurality of ;-personallyoperable members to establish selectivelyablurality of speed drives, including personally-operablemeans for conditioningabontrol mechanism.

Anotherobject of theinvention isto providefa control for an automatic transmission shifter mechanismjhaving a conditioning means Operable into a position 'prerequisiteto'itheoperationof the automatic shifting means and having mechanism inter-controlled with the accelerator] pedal,

so that, when the accelerator pedal is released to one position, the automatic means .jwill produce one "speed drive which may continue thereafter until the accelerator pedalis depressed to apredetermined second position, whereupon the automatic shifterfmeans will'establish another speed drive, which will thereupon continueto be effective until the accelerator pedal is again released to its position requisite-to cause return of the power mechanism and the shift to the first mentioned speed drive. A specific object of the invention 'is' to incorporate said conditioning means with the hand shift lever to be operated by movement of the hand shift lever to a position supplemental to one of the conventional positions thereof.

Another specific object is'to provide means insuring the operation of the power shifting means to a predetermined-oneof its positions whenever the hand shift leveris returned from its supplemental position to one of its standard positions. Another object is toprovide amechanism insuring that the powers-means oan berenclered operable only when;thei=hand shift lever is-movable fromna selected one of its standard positions to said. position supplemental;.-thereto,land 'to' insure further that, when the handlshift lever-is returned to any of its standard. positions, the power mechanism will ,cause itsshift to establish apredeterminedrone of its speed drives.

Another; object. of I theinvention is to; provide! a control for a power shifter wherein, dependent upon the speed of-th'e'vehicle at arate above a predetermined value, the power shifting means may. be operated. to one-.positionby movement of the acceleratorpedaltoan extreme position, and heldin such speed ratio until the accelerator pedal thereafterwagiain;moved to an extreme position, irrespective of the speedof the vehicle.

Specifically, it is an object of the invention to accomplish the foregoing in either one of two ways, to-wit, where the accelerator pedal is movable to one of its extreme positions to cause one speed drive to be established and is moved to the other of its extreme positions to restore the first speed drive; and alternatively to provide that, where the accelerator pedal is moved to one of its extreme positions, the power means will establish one of its speed drives, and where, thereafter, the accelerator pedal is returned to the same one of its extreme positions, the power means will be operated to restore its first speed drive.

Another object is to provide supplemental movement of the hand gear shifting lever to an automatic position, and to provide automatic control of the power shift thereafter under regulation of the accelerator pedal; and more specifically to provide automatic shift by movement of the accelerator pedal to extreme positions after the vehicle has attained a predetermined speed.

An object of the invention is to provide a power-operated shifter control wherein shifting may be effected as a result of the interruption of torque transmitted through gearing; and especially it is an object to provide manual control that, in one action, energizes the power shifter device and interrupts the torque transmitted through the gearing so that the shifting can take place in controlled timed order.

Other objects of the invention include the provision of accelerator pedal operated switch means that attain the functions aforesaid of an accelerator switch, and particularly one wherein such functions are attained in a simple and relatively inexpensive structure.

A further object is to provide a control having the functions of pre-energizing the power shifting means, and in timed relation thereto interrupting the torque transmitted through the gearing, wherein the power means flexes a spring-like means a predetermined degree when the power means is initially energized, so that the spring means applies energy to aid the shift when torque is interrupted; and to provide such a spring or spring-like means that may be flexed a predetermined extent to permit full travel of the power means, although the toothed elements of the transmission are not fully intermeshable at the time the power means so shifts them, whereby the shifting can be completed by the spring means upon substantial synchronization of the toothed elements. A further and specific object is to provide a noise reducing feature in the shift means to prevent or to reduce noise in the event the gearing does not immediately mesh when the power means is applied thereto.

Thus, it is an additional object of the present invention to provide a transmission control including intermating elements operatively interposed between a power means and a transmission, and provided with resilient actuating means for biasing the elements toward and away from engagement to establish and interrupt activation of a transmission gear set.

Another object related to that next above is the provision of means conditioning intermating elements for subsequent engagement to activate a transmission gear set upon manipulation of a personally-operable means to interrupt torque transferral through the transmission.

A further object is to provide a vacuum storing means that will provide ample vacuum for the vacuum-operated shifter means, despite the fact that the shifting may take place when the manifold vacuum is reduced by opening of the carburetor butterfly valve. A particular object is to provide such a vacuum storage means in combination with the aforesaid yieldable means in the shifter arrangement, so that a quick, noiseless operation of the vacuum-powered portion of the shifting means may take place, and store energy for completion of the shift in the yieldable spring means, whereby the latter may complete the shift while the vacuum means holds the spring means in energized shifting condition. Another object of the vacuum storage feature is to render available a sufiicient vacuum for effecting the shifting of the vacuum power means of the shifter device immediately during a part of the releasing action of the accelerator pedal and before the butterfly valve is completely closed, whereby, when torque through the mechanism is interrupted, the power means will be immediately capable of effecting the shift.

Another object of the invention is to provide a throttle closing mechanism that is operated by a slight supplemental movement of the accelerator pedal from its normally maximum depressed position. Stated somewhat more particularly, it is an object of the invention to provide a means to interrupt torque and to restore maximum vacuum conditions by substantially full depression of the accelerator pedal. A specific object in this mechanism is to provide a sensible distinction between the supplemental depressing opcration of the accelerator pedal and the normal depressing operation of the accelerator pedal.

Another object is to provide a control including a switch mechanism operated by the accelerator pedal, and a butterfly valve control operated by the accelerator pedal, so arranged that, when the accelerator pedal is operated to an extreme position, the control will operate to effect a shifting of the power means which will thereafter be maintained through normal accelerator operation until the accelerator pedal is again moved to an extreme position.

Many other objects will appear from the description to follow.

In the drawings:

Figure l is a somewhat schematic view of the control with the related parts of an automobile (non-energized portions of the electrical circuit being shown in dotted lines) Figure 2 is a horizontal medial section through the overdrive shifter mechanism and rear axle system, showing the mechanism in its overdriving position;

Figure 3 is a fragmentary section of the overdrive shifting mechanism after initial energization to shift to direct drive position;

Figure 4 is a view similar to Figure 3 showing the overdrive power means fully shifted, but the shifter mechanism in temporary locked out position owing to lack of intermeshing of the clutch teeth;

Figure 5 is a view similar to Figures 3 and 4, but showing a full engagement of the clutch of the overdrive shifter to obtain direct drive speed ratio;

Figure 6 is a somewhat enlarged view of the compound overdrive collar shifter lever;

Figure 7 is a view of the compound shifter lever, taken from the right of Figure 6 and turned Figure 8 is a sectionalized perspective view of the overdrive clutch collar, showing both the movable and the fixed elements with which it is selectively engageable;

Figure 9 is an enlarged partly broken away section of the overdrive clutch mechanism,*ishown Figure is a view similar to Figure 9 showing the clutch collar in fully engaged direct drive position and corresponding to Figure 6;

Figure 11 is a transverse view of the clutch collar mechanism, taken on the line |lll of Figure 9;

Figure 12 is a view similar to Figure'll, but taken on the line l2 |2 of Figure '10, showing full engagement of the clutch teeth;

Figure 13 is an enlarged plan view of the lower end of the steering column shifter control shaft and shifter arms actuated thereby as shown in Figure 1 including the associated selector switch which is turned 90 from normal position to facilitate illustrating a horizontal section thereof,vthe mechanism being shown in overdrive;

Figure 14 is a view of the lower end of the steering column shifter control shaft assembly similar to Figure 13, with the lower bearing of the shifter control shaft in section, with the selector switch cover in section, and with the shifter mechanism in third speed (direct drive) position;

Figure 15 is a view of the lower end of the shifter control shaft mechanism exclusive of the selector switch, similar to Figure 14 but with the shifter control shaft in upper neutral position;

Figure 16 is a transverse section through the lower bearing for the shifter control shaft, taken on the line l6l 6 of Figure 15;

Figure 17 is a perspective view of the lower end of the shifter control shaft, with the cross pin, and showing the upper end of the selector switch actuating pin;

Figure 18 is a section through the shifter arm hub assembly on the line I8l8 of Figure 13;

Figure 19 is a plan view of the selector switch mechanism;

Figure 20 is a transverse section through the selector switch mechanism, taken on the line 2020 of Figure 19;

Figure 21 is a fragmentary plan view of a typical three speeds forward and reverse automobile transmission;

Figure 22 is a section on the line 22-22 of Figure 21, showing the selector lock mechanism of this transmission;

Figure 23 is a side elevation, partly broken away, of the upper end of the steering column, shifter control shaft, and the shifter shaft handle;

Figure 24 is an axial section through the shifter control shaft at its upper end, taken on the line 2424 of Figure 23;

Figure 25 is a diagrammatic view of the shifter handle, showing its several operative positions;

Figure 26 is a somewhat diagrammatic view in section of the assembly, controlled by the accelerator pedal, shown in released position of the accelerator pedal;

Figure 27 is a view similar to Figure 26 of the accelerator pedal assembly, with the pedal shown substantially in an intermediate depressed position;

Figure 28 is a View of the accelerator pedal assembly shown in maximum normal depressed position of the accelerator pedal;

Figure 29 is a view of the accelerator pedal assembly withthe accelerator pedal in extra depressed position;

Figure 30 is a sectional view throughthe carburetor butterfly valve and operating l nkage,

'6 taken substantially :onthe. :liner3 flee-3 0, :of Figure 26;

I {Figure .31 is :a -'p1an;view.;of the; governor and itsswitch;

Figure 32 is a broken vertical: section-through the governor and its switch, taken on the line 33 2--'32 f Figure 31 Figure 33 is a" transverse section through the upper end of .thegovernor switch,=taken.on the line 3333 of Figure 32;

f-Figure 34 is: a transverse section "throughthe power itake-off means of the. governor, taken on theline 34-34'at thebottom of Figure32;

.Figure' 35 isra section through the :powertakeoff means fromtheapropeller shaft'of; the vehicle to the "governor and speedometer operating cable;

Figure-36is a transverse ;view through oneof 1 the governor switches;

"Figure :37 is a'*transverse view through :the

overdrive imechanism, showing .the two limit (switches of '::the overdrivaand taken on the line 3l-3'I of Figure 2;

Figure '38jis a front elevation of .the accelerator switch;

Figure 39 is a transverse section '-through =the right side of the accelerator switch as it appears in Figure'38;

Figure 40 is another transverse section through the accelerator switch at the same pointeofthe section of Fi ure 39, butshowing the accelerator switch in position wherein theaccelerator pedal is depressed vsubstantially to the intermediate position of Figure 27 "Figure41 is a SGCtiOIILthI'Ol-IghIthC middlefiof the accelerator switch, takenon'thexlinei4l+4l of Figure 38, but showing the condition of the switch where the accelerator pedalzis depressed to the position of Figure 29;

"F ure 42 is a front view of the accelerator switch mechanism similar .to'Figure38, but with the front panel removed, the section being taken on the line 42-42 of Figure39;

Figure 43 .is a transverse horizontal section through the bottom of the accelerator switch,

taken onthe line'43-43 of Figure 38;

Figure 44 is a perspective view of :the accelerator switch operatingshaft and crank: arm assembly;

Figure :45 is a view partly inrmedial section .throughthe selector valve;

Figure 46 is a transverse-sectionthrough the selector valve, taken on the line :46-46 of'Figure 45;

Figure '47 is a transverse. section :through the selectorvalvataken on the line4-1--.41of Fig- ..ure 45 Figure 48 is an end view of thes'elector valve,

ztaken 'fromthe line.;48.48 ofFigure 45;

'top of the vacuum tank, taken on the line 54-54 of Figure 53;

Figure 55 is a transverse section through the bottom of the vacuum tank, taken on the line 5555 of Figure 52;

Figure 56 is a somewhat schematic view of a modified form of shifter control with the related parts of an automobile (non-energized portions of the electrical circuit being shown in dotted lines);

Figure 57 is a top plan view of the governor switch, taken on the line 51-51 of Figure 56;

Figure 58 is an enlarged plan view of the lower end of the shift control shaft in the modification with the associated selector switch turned 90 from normal position and shown in horizontal section with the other parts partly broken away, the shift being in its overdrive position;

Figure 59 is a transverse section, taken on the line 5959 of Figure 58, through the lower bearing of the shift control shaft, showing the limiting pin construction for the shifter control shaft;

Figure 60 is a side elevation of the limit pin control and adjacent parts, as they would appear from the underside of Figure 58, but with the pin in overdrive position;

Figure 61 is a sectional view of the lower end of the shifter control shaft and its lower bearing, taken approximately on the line 6|6I of Figure 60;

Figure 62 is a section similar to Figure 61, but showing the shifter control shaft and limit pin in third speed (direct drive) position;

Figure 63 is a view similar to Figure 61 and Figure 62, but showing the shifter control shaft 4 in its neutral position;

Figure 64 is a transverse section through the lower bearing for the shifter control shaft, taken on the line 6464 of Figure 63;

Figure 65 is a front elevation of the accelerator switch of this modification;

Figure 66 is a transverse vertical section through the selector switch, taken on the line 6666 at the right side of Figure 65;

Figure 6'7 is a section similar to Figure 66 of the accelerator switch, but showing the position when the accelerator pedal is partl depressed;

Figure 68 is a section on the line 6868 to the left of Figure 66;

Figure 69 is a transverse horizontal section through the bottom of the accelerator switch on the line 6969 of Figure 65;

Figure 70 is a perspective view of the accelerator switch operating cam shaft and crank;

Figure 71 is a diagrammatic illustration of the electrical circuits and associated controls of Figure 1 (non-energized circuits being shown in broken lines); and

Figure 72 is a diagrammatic illustration of the electrical circuits and associated controls of Figure 56 (non-energized circuits being shown in broken lines) The following description is of the illustrated embodiments of the invention, wherein the control is applied to an overdrive for use in supplement to a conventional manually-operated change-speed transmission, associated with a pedally-operated clutch and a pedally-operated accelerator. Also the embodiment shows a vacuum-operated overdrive, and electrical control devices relayin to a vacuum power mechanism the sequence of operations desired. These particular elements of the embodiments are combined and improved in novel ways; but, as is known in the art, there are numerous well known 8 substitutes for these elements, and such substitutes are intended to be embodied in the broader claims.

General assembly Figure 1 shows schematically parts of an automobile. There is an engine E, mounted on a frame F. The engine drives through a clutch CL, controlled by a clutch pedal P, to a three speeds forward and reverse speed selective sliding gear transmission T, from which a propeller shaft PS leads. The shaft PS enters a combination differential and overdrive housing OD, from which the axles extend laterally. Thus, in the illustration, there is a conventional transmission T, plus an overdrive; but, in a broader sense, both of these jointly constitute the transmission.

The overdrive illustrated is of the vacuum operated type, deriving vacuum (i. e., a subatmospheric pressure) from an intake manifold M, of the engine E, with which manifold a carburetor C is associated. The manifold M is connected to a vacuum trapping tank VT, that, in turn, is connected to an electromagnetic selector valve SV. The valve SV is oppositely connected to the ends of an overdrive power cylinder ODC.

The selector valve SV is the relay by which an electrical control system is interconnected into the vacuum system. The selector valve, therefore, has movable elements that are moved by the electrical control system, and find reflection in the corresponding elements of the vacuum system. To this extent, the selector valve itself constitutes a power-operated means actuated by the electrical system in a given order, to obtain a shift; although, in a more restricted sense, the power-operated means in the vacuum power means, with or without the selector valve. In certain types of transmission, and of overdrive, the electrical mechanism directly produces the shift, without relaying through vacuum power means.

The electrical system includes six switches in the full embodiment of Figure 1. There is a selector switch SW positioned in response to preetermined movements of the manual shift lever. As stated, the illustration is of a conventional three speeds forward and reverse sliding gear type of transmission, controlled by a steering column mounted hand lever. The selector switch SW has two positions, one to condition the system for a first speed ratio or drive and the other to condition it for choice of either the first ratio or a second speed ratio or drive. In the illustrated embodiment, especial mechanism is provided to limit the power shift to provide a fourth ratio drive obtainable only after the third (direct drive) speed ratio; and, in such case, the two ratios controlled by the system are the conventionally designated third speed and a fourth speed, the latter being an overdrive. When the hand lever is in third speed drive position, the selector switch SW is in position to preselect third speed drive, which corresponds to the normal situation arising from conventional shifting to third speed. When the hand lever is released in third speed position, and that only, it is automatically displaced to a supplemental position, without return from third speed position to neutral; and, in this supplemental position, it moves the selector switch SW to position to pro-condition the system for shift to the second poweroperated speed, here overdrive ratio, or back to the third speed direct drive.

The electrical system includes also an interrupter'switch IS operated bydepression of the clutch pedal P; and hence closed by a torque interrupting operation that disestablishes drive through the transmission. The electrical system associates the-interrupter switch and the selector switch SW in its standard position, so that the selector valve SV establishes direct or third speed drive, the first of the. two power'drives, when the selector switch is in direct drive position and the interrupter switch is operated simultaneously or coordinately. As thetorque breaking. operation, whether manually or automatically performed, by a manual clutch; a power clutch, or a fluid-coupling, always accompanies any normal stopping or initial starting of the vehicle, the control means will'always assure direct drive when starting; and also this arrangement enables the operator to obtain direct drive at willby breaking the torque and displacing the handle to one of its normal positions outside thesupplemental position.

The electrical system includes also a governor. or speed responsive switch 6-. This switch is' held. in one position when the speed is below a critical value, and in another position when the speed is above critical value, the expression critical value encompassing the conventionally provided differential where such is provided for the purpose, among other things of avoiding short cycling when the speed rapidly passes back and forth across the maize or break value. The governor is operated. by one of the transmission shafts; such as an output shaft.

Theelectrical system includes also an accelerator pedal operated switch mechanism AS. The

first phase of this-mechanism closes a switch between a predetermined intermediate accelerator pedal position and the fully released position. This switch is connected with the governor switch G, and the selector switch SW in its second or supplemental position, to operate the selector valve SV to obtain supplemental or overdrive ratio whenever these switches are all closed. Hence, after movement of the hand lever to third speed position, and its release to supplemental position, and after the vehicle attains a predetermined speed, the operator may manually attain supplemental speed, which involves his releasing the accelerator pedal. As the circuits are closed before full release of the pedal, the power shifting means can be fully energized, despite lag in the vacuum operated parts of the system, by approximately the time the accelerator pedal reaches fully released position.

In a shifting of the usual typical speed change shifters such as illustrated, where a shiftable toothed member is subjected to torque through the transmission, when it is engaged in either position, there is apinch between the teeth The other or second phase of the accelerator switch is closed upon extreme depression of the accelerator pedal, and'it is also associated with the governor switch and the selector switch in its supplemental position. The circuit through the second accelerator switch energizes the first or standardrati'o part of the selector valve SV, to give a manuallyandselectively operable kickreduction, and also a. momentary vacuum in-" crease, as further functions of the extreme depression of the pedaL- These functions are ob.-- tained by theillustrated embodiment of the invention, by a mechanism that quickly moves the. carburetor butterfly valve toclosed position when 3 the accelerator pedal is moved from its normally full throttleposition of depression. to the ex-- treme depressed. position, the operation. over lapping the closure of the kicks-back switch means of. the accelerator switch AS.

Limit switchesLSland LS2 operated by mechanism generally indicatedby the letters LS. are provided toopen each energizingcircuit. when the;

shift is fully moved into. the corresponding drive positionand vacuum, and, as. the fun-description will show, quickens an. opposite. shift by relieving; vacuum on the side of the power meansthat, for

opposite shift, must be at high (atmospheric) pressure.

In a modification; the governor switch G. has contacts for both its low speeds and its high.

speeds; these contacts being ultimately connected to opposite sides of theselector; valve.i

The accelerator switch AS has a switch means connected with each governor contact; but the high speed governor contact also passes through the selector switch SW in its second: position.

leased position. By this-arrangement, theop erator obtains the first. speed drive. by release of 1 the accelerator pedal, when the vehicle is moving. below the critical governor speed, and obtainsthe second speed. by the same operation when-the vehicle is moving above the critical; speed.

In order to preventan unexpectedefiecting. of

the second'speed drive whenever the handle is.

shifted in standard manner to establish'the first speed, the accelerator'pedal is released, and. the vehicle is traveling above the critical speed,

means is added to prevent shifting of the selector switch tosecond position when the handle is. moved to first speed drive position and released.

at the time the accelerator pedal is released.

' Only by a depression and release of theaccelerator pedal, subsequent to establishment of the. first speed, can the power shift produce the second speed drive- To provide a convenient kick-back for this. modification, to return the power shift toits first speed despite vehicle speed above the critical value, the high speed contact of'the governor is also connected to the'first speed side ofthe selector switch SW, and thence to the first speed switchmeans of the'accelerator switch AS. When the shifter handle is drawn to directdrive (i. e.,

third speed) position and the accelerator pedal.

is released, the firstspeedxdrive of the poweroperated' means will always be obtained.

Other and detailed functions of the over-all mechanism and its elements-will be developed in.

the following description.

The overdrive- In Figure 2,,the; propeller shaft PS isshown as entering. the housingfor the overdrive OD and for the differential. As is indicated, the propeller shaft has a pinion gear that drives a ring gear 90; A generally cylindrical planet gear cage 91 This insures. economy of electricity is attached to the ring gear 90, and terminates in a sleeve 92 that, as will appear, has rotatable bearing upon a splined shaft concentric with the ring gear, which splined shaft, in turn, is rotatably mounted upon one of the axles.

The planet gear cage 9I supports a. plurality of planetary gears 94 that are rotatable on stud shafts 95 projecting from the cage 9I. These planetary gears are enmeshed with a sun gear 96, and also with an internal ring gear 91, which latter is mounted upon a rotatable support 98 that carries the differential pinions 99 engaging with the differential gears I and I0 I. The gear I00 is connected to drive the axle I02 and the gear IOI is connected to drive the axle I03.

The sun gear 96 is fixed to a splined shaft I05, which splined shaft provides a mounting for the sleeve 92 as aforesaid, and in turn rotates on the axle I03. The splined shaft I extends to the right in Figure 2 a considerable distance, so as to receive a clutch collar I01. The clutch collar is splined to the splined shaft I05 and is slidable therealong.

As particularly shown in Figures 8 to 12, the sleeve 92 has an annular end face I09 that is disposed opposit the inner end face of the collar I01. The end face I09 of the collar 92 is provided with a plurality of outwardly projecting, circumferentially spaced lugs IIO, there being three shown as this constitutes the preferred number. The lugs I I0 are flanked on either side by recesses, as indicated at III and H2. Preferably, the total length of the lugs IIO from the bottoms of the recesses III and H2 is about one and one-half times the depths of the recesses.

Reference particularly to Figure 8 shows that the clutch collar I 01 has an annular extension II 3 projecting inwardly therefrom. This ring affords a recess of more or less annular nature between its inner circular surface and the outer surface of the splined shaft. The ring portion H3 is provided with a plurality of circumferentially spaced lugs II5 projecting inwardly, these being of the same number as are the lugs I III on the sleeve 92. The lugs II5 are in turn flanked by recesses H6 and H1.

The ring portion I I3 has also external circumferentially spaced lugs II8 that are preferably three in number. The collar I01 slides within a fixed ring I that is attached to the differential housing, as indicated in Figure 2. This ring I20 has an opening I2I to receive the collar I01. The edge of the opening I2I is provided with a plurality of lugs I22, corresponding in number spacing to the lugs IIB. These lugs I22 project inwardly toward the differential beyond the face I23 of the ring I20. Each lug I22 is flanked by two recesses I24 and I25.

The operation of the collar I01 is to slide back and forth so as to engage lugs and recesses to fix the collar I01 to the sleeve 92, or alternately to fix the collar I01 to the fixed ring I20. This is a selective movement by which either overdrive or direct drive may be obtained.

The operating mechanism for producing the shift of the collar I01 so as to provide either overdrive or standard drive includes a power mechanism generally indicated at I30. This power mechanism is here exemplified by a vacuum cylinder having opposite ports I3I and I32, and having a movable piston I33 with a piston rod I34. The piston rod I34 is recessed at I35 to provide a notch to receive operatively a round end I36 on a lever I31. This lever I31 is pivoted on a pin I38 that is secured between two outstanding ears of a bracket I39, which bracket is attached to the housing of the overdrive.

As shown in Figure '7, the lever I31 is bifurcated at its lower end. Into this bifurcation, a secondary lever or arm I40 is inserted and is. freely pivotable on the pin I38.

The secondary lever I40 rockably receives av pin I43 that has on its inner end a. shoe I44 that rides in a peripheral groove I45 around the collar I01. Reference to Figure '7 will show that the inner bifurcation of the lever I31 is shorter than the outer one, so that the former does not interfere with the operation of the shoe I44. The; outer arm of the lever I31 has two opposite, angularly separated fingers I46 and I41 that extend to the sides of the pin I43 and are selectively engageable with the pin I 43.

It will be seen that the main lever I31 and the secondary lever I40 are pivoted onto the bracket I39 about the same pin I33, and that the secondary lever I40 has the limited pivotal movement relative to the main lever I31 that is provided by the distance between the two abutment fingers. I46 and I41.

The secondary lever I40 has a flat upper edge- I50. This edge is engaged by a fiat abutment shoe I5I with a guide stem I52 that is slidable in. a hole extending upwardly into the body of the lever I31. A pin I54, constituting an extension of the stem I52, extends upwardly through the hole and through a threaded fitting I55 at the upper end of the lever I31, whereby its upper end is guided. This fitting I55 has a head I56, and is threaded adjustably into the upper end of the lever I31. A lock nut I51 surrounds the threaded fitting I55 outside the lever, so that the fitting may be locked in adjusted position. A stiff coil spring I58 surrounds the pin I54 within the hole of the lever I31 and urges the shoe I5I downwardly against the fiat edge I50 on the secondary lever I40. As is evident, the spring causes the shoe I5I to abut the edge I50 and attempt to maintain the two levers in alignment radially of th pin I38. However, relative rocking movement, as indicated in Figure 4, can be obtained and also during counter-clockwise rotation of the levers, but this causes a compression of the spring I58. The force of the spring may be adjusted by releasing the lock nut I51 and turning the head I56 of the fitting collar I55.

Operation of the power-shifted overdrive The position of Figure 2 is that of overdrive operation. In a previous cycle, low pressure has prevailed on the left side of the piston I33 and it has been moved to the position shown.

In overdrive position, the propeller shaft PS drives the ring gear 90, and, in conventional operation, the upper side of the ring gear in Figure 2 moves downwardly. The planetary gear cage 9| thus moves downwardly at its upper end and upwardly at its lower end in Figure 2; and it similarly moves the stud shafts with the planetary gears 94 thereon. The planetary gears mesh with the sun gear 96 and the internal ring gear 91.

As will appear, the sun gear 96 is held fixed in the overdrive position, and as a result the planetary gears 94 roll around the sun gear 96 upon rotation of the cage SI, and cause the internal ring gear 91 and its support 98 to move more rapidly than does the cage 9|.

As noted, the sun gear 96 ils fixed against rotation in the position of Figure 2. This is occasioned by the fact that the collar I01 is in its outer position. In such position, the lugs IIO on amazes:

the sleeve 92 are disengaged from. their corresponding notches H6, H1 on thecollar I01 and. the lugs II are disengaged from the notches:

with respect'to the casing. As the collar I01 issplined to the splined shaft I05, and as the latter is fixed together with the'sun gear'QG; that gear is held immovable and the previously de-- scribed overdrive operation is produced when the propeller shaft PS rot-ates.

This overdrive is adapted to be operated by'a control having certain characteristics thatwill be hereinafter described. Suflice it to say at the present time that one of the things done by the control will be to-reverse the vacuum and air con ditions operating upon the piston I33, so that the piston moves fromthe position shown in Figure 2 toward the opposite end of the cylinder.

In normal drive, this reversal of the piston I33 may take place while torque is bein transmitted from the-propeller shaft PS to the axles I02 and I33. Such torque applies a rotary thrust force to the collar I81 and tends to bind the lugs II8 against the side walls of with Whichever of the slots I2 or I25 they are engaged. This side wall thrust tends to prevent the ready withdrawal of the collar in an axial direction so as to release the lugs from the slots. Consequently, when the piston begins to move to the right from the position of Figure 2, it will first move to a position such as that shown in Figure 3; In this movement, the lever I31 is rocked about the pin I38, but the secondary lever I40 is not moved because it is retained by the shoe I44, which is held against axial movement by'the collar I01 that resists movement in the manner aforesaid. Consequently, the main lever I31 will be rocked rel-'- atively to the secondary lever I40.

lhis relative rocking movement will cause the upper edge I58 of the secondary lever and the flat shoe I5I to be rocked to the position shown in Figure 3, which additionally compresses the spring I58.

The foregoing relative movement, that is to say, rocking of the main lever'I31, without rockingof the secondary lever I40, will continue until the finger I66 on the main lever engages the pin IE as is specifically indicated in Figure 3. Thereupon, in normal operation, the piston I33 will stop, because the power is ordinarily insufficient to overcome the torque effect that locks the collar 61 to the fixed plate I20. In other words, the continued transmissionof torque through the overdrive and differential mechanisms will nor-- mally prevent the shift of the overdrive from one position to another.

If, whilethe parts are in the positions of Figure 3, the torque is released, the shift may be completed. This torque is readily released by the driver, as by release of the accelerator pedal. When the accelerator pedal is released, there is ordinarily first a reduction of torque and finally areversal of torque as in coasting drive. Such reversal and/or release of torque relieves the pressure between the lugs. I I8 and the side wallsof their respectivevslots in4the1plate: I20, and per-s napsreverses.it:reapplied.v Atthe'instant it iSiI'BJ- lieve'd, the vacuum pressure acting.upon. :the:pis-' ton $331 (or, more accurately, the pressure. differentials acting thereon, by whatever means ob:-

tained) causes a rapid movement of the piston. I33 to the right hand end-of; the. cylinder, as. shown in Figure 4. Simultaneously; the spring;

I58 tends-t0 realignthe levers I-31 and I40.

Asthe collar I01 approaches its-inner or left hand posi-tion, projecting ends of the lugs I I5 on.

theannularpart: II3' of the; collar I01v mayabutthe-face I09 of the sleeve 92; and, atthe same time, the ends of the lugs I I0 will engage the an! nula-r faceof' the portion II31' of the collar; I0]. When thisoccurs; the partswillbe in the'posie tions of- Figure4, whereinthe'lever I31 is moved. its full stroke bythe overdrive power cylinder ODC, but the secondary lever. I40 isagain: ana

gularly displaced relatively thereto due to the abutting condition above-described. The'pin I43 is in engagement with the finger I46 on the main.

lever I31, and the compression. spring I58, actingthrough theshoe I5 I, is applying a force that tendsto cause the secondary lever I 10 to move into alignment with themain lever I31 a condition shown in Figures 2, 5 and 6 The end abutment of the lugs H0 and H5 on the respective surfaces of their companion memhers is a relatively noiseless engagement, despite therelative rotative movement'betweenthe parts. The relative speeds of the sleeve 02 and of the collar I01 are determined by the torqueconditions at the time of shift. It may be assumed first that the sun gear 96 1s driving the splined shaft and the collar IOT- at higher speeds than those of the sleeve-92. In this'case, the lugs II5 will movearound the'face I09- of the sleeve 9-2 until the lugs II5 abut the lugs IIO: Thereupon, the action of the spring I 58 upon the secondary lever I40 will cause the lever I40 to align-itselfwith the lever I31; 111 which operation'itmoves the pin I43and the sleeve IM'to'shift the collar I31 from the position of Figure 4 to the position completed, the lugs I I0 being engaged in the notches I56, and the lugs H5 in the notches II 2. It will be evident that, if the relative rotation between the sleeve QZand the collar I01 were opposite to that described; the lugs I I0 could have -entered the notches H1, and the lugs II5 entered thenotches I II.

Briefly, the direct transmitting driveoperates byhaving the sleeve92'driven by'the ringgear 90 fixedto the collar I01, and hence splinedto the splined shaft I05vand to the sun gear 95. Thus the sun'gear'and' the" planetary gears are caused to rotate in unison and to" drive the internal overdrive ring gear 91 at the same speed as the main ring gear rotates.

When it is desired tof shift from direct drive to overdrive,,the operation is a direct opposite to that previously described. When the piston 1331s moved from the position of Figure 5, it"

is, relieved as by brief releaseof the accelerator.

pedal, the piston. may continue its movement .to the left and the lever mechanism willshift. the

In this position'the direct drive'is 

